RT9261_07 Datasheet, PDF (1/12 Pages) Richtek Technology Corporation – VFM Step-Up DC/DC Converter

Preliminary
RT9261/A
VFM Step-Up DC/DC Converter
General Description
Features
The RT9261 Series are VFM Step-up DC/DC ICs with ultra
low supply current by CMOS process and suitable for
use with battery-powered instruments.
The RT9261 IC consists of an oscillator, a VFM control
circuit, a driver transistor (LX switch), a reference voltage
unit, an error amplifier, resistors for voltage detection, and
a LX switch protection circuit. A low ripple and high
efficiency step-up DC/DC converter can be constructed of
this RT9261 IC with only three external components.
The RT9261A IC provides with a drive pin (EXT) for an
z Minimal Number of External Components ( Only
an Inductor, a Diode, and a Capacitor)
z Ultra Low Input Current ( 5μA at Switch Off)
z ± 2% High Output Voltage Accuracy
z Low Ripple and Low Noise
z Low Start-up Voltage, 0.85V at 1mA
z 75% Efficiency with Low Cost Inductor
z +50 ppm/ °C Low Temperature-Drift
z SOT-89 and SOT-23-5 Small Packages
z RoHS Compliant and 100% Lead (Pb)-Free
external transistor, so that a power transistor can be _Applications
externally applied. Therefore, the RT9261A IC is
recommended for applications where large currents are
required. EN pin enables circuit to set the standby supply
current at a maximum of 0.5μA.
z Power source for battery-powered equipment
z Power source for cameras, camcorders, VCRs, PDAs,
pagers, electronic data banks, and hand-held
communication equipment
Ordering Information
z Power source for applications, which require higher
voltage than that of batteries used in the appliances
RT9261/A-
Package Type
B : SOT-23-5
Marking Information
X : SOT-89
For marking information, contact our sales representative
Operating Temperature Range
directly or through a RichTek distributor located in your
P : Pb Free with Commercial Standard
G : Green (Halogen Free with Commer- ^{area, otherwise visit our website for detail.}
cial Standard)
Output Voltage
15 : 1.5V
16 : 1.6V
:
49 : 4.9V
50 : 5.0V
Pin Configurations
(TOP VIEW)
Use external switch
Use internal switch
Note :
RichTek Pb-free and Green products are :
`RoHS compliant and compatible with the current require-
ments of IPC/JEDEC J-STD-020.
`Suitable for use in SnPb or Pb-free soldering processes.
`100% matte tin (Sn) plating.
123
123
GND VOUT _LX
(TAB)
RT9261-††CX
GND VOUT EXT
(TAB)
RT9261A-††CX
SOT-89
DS9261/A-12 March 2007
www.richtek.com
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